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Thus, spermatogenesis is the male version of gametogenesis, of which the female equivalent is oogenesis. In mammals it occurs in the seminiferous tubules of the male testes in a stepwise fashion. Spermatogenesis is highly dependent upon optimal conditions for the process to occur correctly, and is essential for sexual reproduction .
Gametogenesis, the development of diploid germ cells into either haploid eggs or sperm (respectively oogenesis and spermatogenesis) is different for each species but the general stages are similar. Oogenesis and spermatogenesis have many features in common, they both involve: Meiosis; Extensive morphological differentiation
Spermatogonia undergo spermatogenesis to form mature spermatozoa in the seminiferous tubules of the testicles. There are three subtypes of spermatogonia in humans: Type A (dark) cells, with dark nuclei. These cells are reserve spermatogonial stem cells which do not usually undergo active mitosis. Type A (pale) cells, with pale nuclei.
Type Ap spermatogonia repeatedly divide mitotically to produce identical cell clones linked by cytoplasmic bridges (in rodents, not in primates such as humans). The connections between cells allow development to be synchronized. When repeated division ceases, the cells differentiate into type B spermatogonia.
Oogenesis (/ ˌ oʊ. ə ˈ dʒ ɛ n ɪ s ɪ s /) or ovogenesis is the differentiation of the ovum (egg cell) into a cell competent to further develop when fertilized. [1] It is developed from the primary oocyte by maturation.
Sperm are produced by spermatogenesis and eggs are produced by oogenesis. During gametogenesis in mammals numerous genes encoding proteins that participate in DNA repair mechanisms exhibit enhanced or specialized expression. [18]
This occurs between the time they inhabit the forming gonads on the genital ridge to the time they migrate to the basement membrane of the seminiferous cords. Gonocyte development consists of several phases of cell proliferation, differentiation, migration and apoptosis. [4] [5] The abnormal development of gonocytes leads to fertility-related ...
Human sperm stained for semen quality testing. Sperm quantity and quality are the main parameters in semen quality, which is a measure of the ability of semen to accomplish fertilization. Thus, in humans, it is a measure of fertility in a man. The genetic quality of sperm, as well as its volume and motility, all typically decrease with age. [17]